Treatment of small metal-coated parts



'Junell, 1929. E N 1317.220v

TREATMENT OF SMALL METAL COATED PARTS Filed Oct. 13, 1926 Fig. l. 3

9 A. J 7 l0 y "5 j 6 E E 1 2:1 6

Inventor:

Charl es E.Jones,

His Attorney.-

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Patented dune ltl tle T A T CmLE-fi E. JONES, 0F SCHED IECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIQ v COMPANY, A COORATION OF NEW YORK.

TREATMENT OF $13 METAL-COATED PARTS.

application filed October 13, 1926. Serial No. 141,395.

The present invention relates to improvements in the process of tinning or coating small metal parts of the type usually employed in the assembly of radio or like apparatus, and more particularly to a metho d of treating such small metal parts 1mmed1 ately after they have been taken out of a tinning or galvanizing bath. Heretofore in the tinning or galvanizing of small metal parts considerable difiiculty has been encountered in removing excess metal from the parts and also in preventing the parts fromsticking or fusing together. For example, in tinning small parts it has been customary to place them in a wire basket which 1s momentaril immersed in molten metal. After removing the basket from the molten metal the excess coating metal is removed by agitating or shaking the basket and the parts are'then poured out on to an inclined wire screen which carries the coated parts into a cooling fluid, such as water, or the like. With this arrangement, considerable excess metal adheres to the coated material, and frequently the parts become fused together into a solid mass.

According to the present invention, after .an excess'portion of the coating metal has been removed, as in the old method, by shaking the basket container, the small metal parts, while still very hot, are poured through a hopper on to an inclined chute which may, if desired, be heated to an elevated temperature. An air pipe is fitted into the upper end of the chute, and as the metal parts fall through the hopper and towards the bottom of thechute, they are subjected to an air blast at a pressure of about 80 pounds to the square inch. The air blast removes all excess metal, provides a smooth, bright coating, and slice tively prevents the plated parts from adher' ing or fusing together.

The novel features which are characteristic of m invention will best be understood from re erence to the following specification taken in connection with the accompanying drawing, in which Fig. 1 represents aview, partly in section and partly in elevation, of the apparatuswhereby my invention may be carried into effect, while Fig. 2 is a perspective view of the air sup ly pipe which is fitted into the upper end 0 the chute.

Referring to the drawing, I have indicated at 1 a tank which may be partially filled with water or other cooling medium, and on which an inclined chute 2 is supported. The chute is substantially rectangular in crosssection and is provided near the upper end thereof with a hopper 3,'and a pipe 4 which extends across the entire width of the chute. The pipe 4 is perforated in a length! wise direction, as indicated in Fig. 2, and

is connected to a suitable source of air pressure through the pipes 5. A valve 6 is mounted in the air pipe and may be manually operated to control the supply of air to the pipe 4. The lower end of "chute 2 is provided with a wire mesh screen 7, which extends downwardly towards the tank 1.

Screen 7 directs the material from chute'2 into a wire basket 8 which rests on the bottom of tank 1 and at the same time serves to relieve the air pressure inchute 2 and thereby prevent the water from being blown out of the tank; I I

In the operation of the device, the valve 6 is opened and air pressure of about 80 pounds per square inch is directed. into the chute. The tinned or metal coated parts are then poured while still at an elevated temperature, into the hopper 3. As the metal coated material falls from the hopper towards the bottom 9 of the chute, the air blast from pipe 4 is applied directly to the metal coated part-s driving themv towards the lower end of the chute and into the tank 1. The air blast applied in this manner prevents the small metal parts from adhering together and at the same time provides a'srnooth metal coating entirely free from excess metal.

For the successful operation of my method,

it is essential that the metal coated material be poured into the hopper 3 before't-he metal has cooled appreciably,as otherwise it would be impossible to prevent fusion of the metal parts. I would found itadvantageous, although not absolutely essential, to heat the chute during the operation of the process to a temperature in the neighborhood of 700 F. This may,be done by means of an electric heat-ing coil 10. or if desired, by other suitable means, as for example, a steam coil or a gas flame applied directly to the external part of the chute. Ordinarily either cold or hot air may be employed in the air blast, but it will be found preferable to use a heated air blast in order to assist in maintaining the coated metal at a high temperature during its passage through the chute.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. The method of treating metal parts which have been coated by immersion in liquid metal, which comprises pouring the metal-coated parts, while still at an elevated temperature, into a chute and applying an air blast to the metal-coated parts at the upper end of such chute.

2. The method of treating metal parts which have been coated by immersion in liquid metal, which comprises pouring said coated parts while still at an elevated temperature onto a downwardly inclined surface and into the path of an air blast directed downwardly and substantially parallel to said surface.

In witness whereof, Ihave hereunto set my hand this 12th day of October, 1926.

CHARLES E. JONES. 

